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Thanks for your reply and I am trying to learn as I go, along with the contractor. I think hybrid systems are fairly new to this area as 3 out of the 4 contractors I had come out said that they had heard of heat pumps but weren't familar with them. The contractor I hired has the most experience in this area with heat pumps but is still learning. The Evolution thermostat does not calculate the best balance point but has a lot of other nice features as far as I can tell being a newcomer to this field. I will see if I can track down the LoadCalc software.

Originally Posted by arc8

I am looking for the best Economic balance point.

Think of this a constructive criticism reply.

First you needed to have done a HeatLoad calculation, especially by your contractor! You need this to figure out your particular thermal balance pt and your economic balance pt. And this brings me to, how in h-- did they figure out your equipment sized??? The Evolution is a great system, but it doesn't mean you are getting the best system for your house!!!

!!It's very important to sized a whole system and fit it to your existing home!!

Now the equipment: The economic balance pt must be less than your thermal balance point. But how would you know that if you don't have a LoadCalc to guide you!
With a loadcalc in one hand and the right equipment selected to meet the need for efficiency and comfort's sake, you can determine 1. how much the heat pump can handle (at what temp pt to shut off), 2. when you want the gas furnace to come on (at what temp pt to turn on), and 3. if supplemental heat is required (sometimes it cost less to run the heatpump and resistive heat together than a gas furnace to a certain pt.).

But i could be all wrong about this idea if the Hybrid Heat system has a minicomputer built-in to figure this all out!

Under the advanced settings there is a selection where you can choose a heat pump lockout temperature. I think it is under Advanced/Settings/Hybrid Heat. If you can't find it let me know and I will try it again at home and reply.
My default setting was none which I think means the heat pump would run as long as it could keep up with heating demands and then switch to the furnace if it could not keep up. I have set mine for 28 deg for now.

My contractor spoke with the local Bryant rep and he said that there are two schools of thought on the balance point for this area - SE Michigan. One is that you have no heat pump lockout temp selected and let the heat pump run as much as possible until it can't keep up and then the furnace will take over as the heat pump will be cheaper to run than the furnace at any outdoor temperature that the heat pump can provide heat for. The other school is that the defrost cycle uses a good amount of electricity and also to save wear and tear on the heat pump, a balance point of 28-30 is a good setting. My contractor said they don't have a long history of information to go on in this area about the wear and tear/defrost cycle but he is going to look for software to provide more guidance.

Since I am a BRyant rep please go to page 2 and read my reply. you are way overthinking this decision. I think a good train of thought for you is to lower it until it in not able to keep you comfortable and then move it up a couple of degrees.

There is no reasonable economic balance point where the fossil fuel furnace is more efficient than the heat pump, until it's about -10F outside, (equal to the furnace). Balance point is and always will be the point where there the heat pump can no longer satisfy the heating demand alone. When the room temp falls below the setpoint, you have fallen below the balance point, and will require back-up heating to maintain the same setpoint.

You write that:
"when the heat pump's COP is at .95 "

The factor that you have not consideed in your analysis is the Cost of Power.

However, the Conversion of Power (COP) is only one factor in the equation.
At lower temps the Heat Pump COP becomes very low - you sited 0.95.
If raw energy cost (BTU cost) from electricty is 2X the NG cost, the cross over point for the cost of home heating will not be the heat pump COP number.

Neither of those consider the "comfort factor" of having blowing hot air, and that is homeowner subjective.